Macromolecular compounds have come to be used in various fields not only as a general purpose structure-forming material but also as a value added type material having high function and performance, and the importance of producing polymeric materials under precise design is increasing. Also in an organic-inorganic composite material containing silsesquioxane as an inorganic component, it is very important to create a novel functional polymeric material. Such material is obtained by synthesizing a macromolecular compound having a clear structure and precisely analyzing a molecular property thereof and a property as an aggregate respectively to thereby make correlation between both clear and setting it as a design guideline. However, conventional organic-inorganic composite materials do not necessarily contain a polymer which is controlled in a structure as an organic component, and a lot of them is obtained by mechanically blending silsesquioxane with organic polymers, so that it used to be very difficult to control the structure of composite materials as molecular assemblies.